1. Technical Field
This invention relates to third generation mobile telecommunications and, more particularly, to backward compatibility thereof with previous generation mobile telecommunication systems.
2. Discussion of Related Art
The new Third Generation Partnership Project involves the provision of higher data rates and a wide range of telecommunications services, including support for multi-media. It is to be based on the Global System for Mobile communication (GSM) with some major modifications, especially in the radio interface. The third generation network is supposed to support both circuit-switched and packet-switched services. The circuit-switched technology will be based on the current GSM circuit-switched technology, and the packet-switched technology on General Packet Radio Service (GPRS), which is a new packet service for GSM.
The third generation architecture should support mobility management in a general manner. However, there is presently no way to interoperate the planned third generation system with the older generations of mobile systems without making an extensive standardization effort in order to make the new system interoperable with the old systems. For instance, there is a problem to be solved in providing user mobility for the third generation mobile units, which achieve mobility both in the new third generation infrastructure and while at the same time utilizing the earlier generation infrastructure. One solution would be to standardize a signaling methodology that would signal a user identification to the older networks in a way that could be interpreted properly. However, what is needed is a solution that does not need a standardization effort.